P0141

hello, my CEL is on due to code P0141, it started from the moment I took away my cat.. I allready tried to put a new lambda in (but the problem isn't fixed with it , and I'm pretty sure that there isnt an open/short in the wiring from the car.. I got 2 friends who got the same problem..
I've been searching the internet.. but no one seems to post something when the problem is solved..
I know it's the heating circuit from the second lambda, now I need to know how this circuit works.. (internal lambda) is it something like a PTC / NTC ?

thx
Rigo

(sorry for bad English, I'm from Belgium )

grtz

Well, P0141 has nothing to do with the cat. It's a HEATER CIRCUIT problem. Your replacement o2 sensor(lambda) that you installed: was it OE or was it a universal fit that requires cutting and splicing wiring? Is it possible that you crossed any of the wires? Did it plug in properly or did it require some engineering for it to fit?

I did it myself, just cut the former wires and connected the new ones, the colors were the same.. and I'm pretty sure I didn't make a short-circuit while working (battery wasn't connected)
but it is a universal lambda.. my friends have the same code, and there is nothing changed to their oem 2nd lambda... maybe the lambda is getting to hot, and brakes down or something ?
grtz

I still have one new lambda in spare, maybe the problem will be solved if I put this one in and connect a PTC between the two heater wires coming from ecu ? but I need to be sure it is a PTC inside the lambda..

I came to this because i have read that the ecu does have to wait to long to get the pulses from the lambda.. so that means that my lambda doesn't get hot enough.. or maybe it's just to hot, and breakes down... he does transmit a signal though.. (0,1 - 1V)
grtz

Friend, if I were you I would get the proper O2 sensor (American speak for Lambda) with the correct socket on it for your specific vehicle from the dealer before I did anything else. O2 sensors are not created equal, and newer vehicles have much more strict requirements for O2 sensor performance than older ones.

ok, will do that.. but I don't expect that it will work.. because my friends got the same code with oem O2 sensor after taking the cat out...

grtz

Taking the Cat out? THe O2s Heater circuit will not work without the heat of a Cat in the circuit. Besides it is illegal to run a straight pipe, even if it does give a little more power. It will take more than the minute or so allowed by the computer to reach proper temperature and will then light the CEL. The computer measures water temperature to do this, so you need a good high temp thermostat to enable a quick warm up.

On my Mercedes E420 I get this code if I do not allow engine to warm up a bit by revving engine to about 2000 rpm before driving off. This car normally idles at under 500RPM in gear and warms up too slowly if not allowed to rev a bit.